[0001] The present invention relates generally to telecommunications systems and in particular
to methods and systems for allowing a variety of devices desiring IP addresses from
potentially different sources to operate, e.g., on the same local area network.
BACKGROUND
[0002] Communications technologies and uses have greatly changed over the last few decades.
In the fairly recent past, copper wire technologies were the primary mechanism used
for transmitting voice communications over long distances. As computers were introduced
the desire to exchange data between remote sites grew for many purposes, such as those
of businesses, individual users and educational institutions. The introduction of
cable television provided additional options for increasing communications and data
delivery from businesses to the public. As technology continued to move forward, digital
subscriber line (DSL) transmission equipment was introduced which allowed for faster
data transmissions over the existing copper phone wire infrastructure. Additionally,
two way exchanges of information over the cable infrastructure became available to
businesses and the public. These advances have promoted growth in service options
available for use, which in turn increases the need to continue to improve the available
bandwidth for delivering these services, particularly as the quality of video and
overall amount of content available for delivery increases.
[0003] As the consumer electronics industry continues to mature, and the capabilities of
processors increase, more devices have become available for public use that allow
for the transfer of data between devices and more applications have become available
that operate based on this transferred data. Of particular note are the Internet and
local area networks (LANs). These two innovations allow multiple users and multiple
devices to communicate and exchange data between different devices and device types.
With the advent of these devices and capabilities, users increasingly desire to receive
a variety of services over these networks. Some common examples of these services
(or applications) are video on demand (VoD), Internet Protocol television (IPTV) and
audio files. Additionally, many of these services can be received in different formats,
relating to different service quality levels, based upon a variety of parameters.
[0004] Taking advantage of the ongoing improvements to communications, a single user or
users within a household can have various devices that are capable of interacting
with other devices and/or systems through various networks. It is not uncommon for
a household to have personal computers (PCs) 10 and 12, a cell phone 14 and a personal
digital assistant (PDA) 16 all of which are capable of connecting to a wide area network
(WAN) 22 through different interfaces as shown in Figure 1. In this example, PCs 10
and 12 are part of a home local area network (LAN) and are connected to a network
access translation (NAT) router 18 which is part of customer premise equipment (CPE)
gateway (GW) 20, for example, a digital subscriber line (DSL) modem or a cable modem.
The NAT router 18 (or similar device using network access port translation (NAPT))
receives a single WAN IP address which is shared by all of the devices associated
with the NAT router's 18 LAN. To differentiate between devices in its LAN a typical
NAT router 18 uses Address Resolution Protocol (ARP) to obtain the Medium Access Control
(MAC) addresses (given the locally assigned IP addresses from reserved private IP
addresses, e.g., 192.168.x.x) of the devices, e.g., PCs 10 and 12 which are then stored.
Packets can then be transmitted by these locally addressed devices, e.g., PCs 10 and
12, by using ARP and layer 2 switching. This layer 2 switch could be located in CPE
GW 20 or elsewhere in the network. This then allows the CPE GW 20 with router 18 to
provide access for the devices to a WAN 22 by forwarding traffic to IP edge node 26
associated with WAN 22. When local traffic is outgoing to the WAN 22, the packets
pass through the NAPT function in the router 18 wherein the local address is replaced
by a WAN address in the IP source address field. In the opposite direction traffic
from IP edge node 26 is received by CPE GW 20. The received traffic then goes through
the NAPT function within router 18 where the WAN address is replaced by the local
address in the IP destination address field. The router 18 within CPE GW 20 knows
that this traffic address belongs to the local subnet, i.e., from the matching prefix,
and that this local subnet is a LAN of an Ethernet type. The ARP protocol can then
be used to find the Ethernet MAC address of the device (alternatively the Ethernet
MAC address of the device associated with the incoming traffic can be stored from
the initial use of the ARP protocol). For more information regarding ARP, the interested
reader is referred to RFC 826 and RFC 4338 which can be found online at www.ietf.org.
The received traffic is then forwarded to the MAC address. From here traffic from
the PCs 10 and 12, after the desired authentication and approval process, goes to
and can be received from their desired respective correspondent nodes (not shown).
[0005] Also as shown in Figure 1, other household devices can be in communication with correspondent
nodes (not shown) associated with WAN 22, For example, cell phone 14 and PDA 16 can
have a wireless connection to cellular network 24 which represents any of the different
types of cellular networks and the infrastructure used to connect the cellular network
24 with WAN 22, which in turn is in communication with an IP edge node 28 associated
with the WAN 22. At this point, traffic from cell phone 14 and PDA 16, after the desired
authentication and approval process, goes to their desired respective correspondent
nodes (not shown). These devices, cell phone 14 and PDA 16, are considered to be WAN
addressed devices since they are directly assigned their own WAN IP address, e.g.,
cell phone 14 can be assigned a WAN IP address of, for example, 178.12.13.15 from
a source associated with WAN 22, e.g., a dynamic host configuration protocol (DHCP)
server. These WAN addressed devices do not share their IP address with any other devices,
i.e., a single unique IP address is associated with each WAN addressed device. Typically
WAN addressed devices desire their own IP address from a WAN due to being mobile and/or
the device or service desired requires a type of special service or policies that
are difficult to support when "hidden" behind a NAT router. Since Figure 1 is showing
a simplified communications diagram, it is to be understood that there typically would
be a plurality of routers (not shown) within WAN 22 through which communications between
these devices and their respective correspondent nodes (not shown) travel. This concept
also can apply to the travel path for mobile communications enroute to an IP edge
node 28 from their respective originating points.
[0006] As shown in Figure 1, not all of the communication devices are operating within the
same LAN at the user's household. This means that the locally addressed devices, e.g.,
PC 10 and PC 12, are not locally communicating directly with the WAN addressed devices,
e.g., cell phone 14 and wireless PDA 16. It would be useful to have the option to
connect the WAN addressed devices to the LAN and allow these WAN addressed devices
to communicate directly with other devices connected to that LAN, as well as reducing
the load on the wireless access system.
Patent application
EP 1 613 022 A1 discloses a network that accommodates both devices with local IP addresses and devices
with global IP addresses. This is made possible by manipulation of address subnet
masks.
[0007] However, there are currently reasons for not assigning local addresses to WAN addressable
devices. For example, for some devices, typically non-stationary devices, it is not
desirable to have them operating in a locally addressed mode because a user often
wants a device to be reachable from the WAN side to continue to receive all of the
same services currently receivable, e.g., cell phone 14 needs its WAN address to typically
receive all of their subscribed services from the cellular network 24. Also, if one
were able to force all of the devices to have a unique WAN address, the desired number
of IP addresses might not be available since there is a cap on the number of available
addresses in IPv4. Additionally, there are currently hurdles for putting both locally
addressable devices and WAN addressable devices into the same LAN, for example, most
CPE GWs 20 available today are designed to operate in either a locally addressable
mode for all connected devices or in a WAN addressable mode for all connected devices.
When attempting to put both locally addressed devices and WAN addressed devices into
the same LAN there need to be methods for the CPE GW 20 to determine when it should
allocate IP addresses, when the accessed WAN 22 should allocated IP addresses to devices
as well as how to route packets between devices that are locally addressable and those
devices that are WAN addressable.
[0008] Accordingly the exemplary embodiments described herein provide systems and methods
for allowing locally addressed devices and WAN addressed devices to be part of the
same LAN for improving communications between these devices.
SUMMARY
[0009] Systems and methods according to the present invention address this need and others
by providing systems and methods for allowing locally addressed devices and WAN addressed
devices to be part of the same LAN, and provide for local communications therebetween,
in order to improve communications between these devices.
[0010] According to claim 1, a method for allowing both network devices desiring a local
address and network devices desiring a wide area network (WAN) address to obtain Internet
Protocol (IP) addresses via a local area network (LAN) includes: receiving a message
from an end user device connected to the LAN wherein the end user device is requesting
an IP address; determining whether the end user device is a locally addressable device
or a WAN addressable device; forwarding the IP address request toward a WAN if the
end user device is the WAN addressable device; storing, as route entry information,
a returned IP address for the WAN addressable device; and routing information locally
over the LAN which is addressed to the WAN addressable device using the stored route
entry information. Claim 12 concerns a corresponding communications node.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings illustrate exemplary embodiments, wherein:
[0012] Figure 1 depicts connection paths for devices to a wide area network;
[0013] Figure 2 illustrates a connection path for devices through a gateway to a wide area
network according to exemplary embodiments;
[0014] Figure 3 illustrates a customer premise equipment gateway (CPE GW) according to exemplary
embodiments;
[0015] Figure 4 shows dynamic host configuration protocol (DHCP) signaling messages;
[0016] Figure 5 depicts a call flow diagram using DHCP signaling through a CPE GW according
to exemplary embodiments;
[0017] Figure 6 shows a communications node according to exemplary embodiments; and
[0018] Figure 7 illustrates a method flow chart according to exemplary embodiments.
DETAILED DESCRIPTION
[0019] The following detailed description of the exemplary embodiments refers to the accompanying
drawings. The same reference numbers in different drawings identify the same or similar
elements. Also, the following detailed description does not limit the invention. Instead,
the scope of the invention is defined the a pended claims.
[0020] As mentioned above, it is desirable to provide mechanisms and methods that allow,
for example, operating devices that are locally addressable and wide area network
(WAN) addressable devices into a single local area network (LAN) for use at a single
access point which provides access to a WAN. In order to provide context for this
discussion, an exemplary grouping of devices and communication links will now be described
with respect to Figure 2.
[0021] According to exemplary embodiments as shown in Figure 2, the customer premise equipment
gateway (CPE GW) 40 is the access point from an end user's residence to a WAN 22.
CPE GW 40 includes a network access translation (NAT) (or network access port translation
(NAPT)) ability as described above. Additionally, CPE GW 40 is capable of not using
NAT on communications as desired. On the residence side, CPE GW 40 is connected to
LAN 30. LAN 30 is in communications with locally addressed devices, e.g., personal
computers (PCs) 10 and 12 capable of having local Internet Protocol (IP) addresses
assigned, and WAN addressed devices, e.g., cell phone 14 and personal digital assistant
(PDA) 16. Traffic such as IP packets can be tunneled from these devices over the LAN
30 to the CPE GW 40 for forwarding outside of the residence to a variety of correspondent
nodes (not shown) either through or associated with WAN 22. Communications leave CPE
GW 40 and are transmitted to IP Edge node 26 which is typically some type of router.
IP Edge node 26 can act as an entrance or boundary to WAN 22. Additionally, IP Edge
node 26 can be in communications with a dynamic host configuration protocol (DHCP)
server 32 and a Remote Authentication Dial In User Service (RADIUS) server 34. The
DHCP server 32 can be used when attempting to obtain Internet Protocol (IP) addresses
and the RADIUS server 34 can be used for authentication purposes prior to allowing
a user device to obtain an IP address or access to specific services. The CPE GW 40,
according to exemplary embodiments, is designed to allow both WAN addressed devices
and locally addressed devices to communicate with each other in a single LAN 30 and
will be described in more detail below.
[0022] As described above with respect to Figure 2, the CPE GW 40 is the access pint from
a single location, e.g., an end user's residence, to a WAN 22. According to these
exemplary embodiments, CPE GW 40 provides a number of useful features for allowing
locally addressed devices and WAN addressed devices to operate together on LAN 30
and communicate through CPE GW 40 which will now be described in more detail with
respect to Figure 3. According to exemplary embodiments, CPE GW 40 includes a communications
interface 308, a NAT function 306, a DHCP decision function 304 and a router 302.
Each of these components can exchange information as needed. Router 302 includes a
route entry table 310 for storing IP addresses associated with each device in the
LAN 30 and is in communication with both locally addressed devices and WAN addressed
devices over LAN 30. DHCP decision function 304 is used in conjunction with the router
302 to determine if a particular device requesting an IP address via LAN 30 needs
a WAN IP address or a local address provided by the NAT function 306. NAT function
306 is used for providing local IP addresses. Communications interface 308 is the
receiving/forwarding port for communications from/to the WAN 22 through an IP edge
node 26. These exemplary components are used to allow locally addressed devices and
WAN addressed devices to operate together on LAN 30 and to communicate through CPE
GW 40. Exemplary methods for such operations and communications will be described
below.
[0023] According to exemplary embodiments, both locally addressed devices and WAN addressed
devices operate with the same LAN 30 while maintaining local LAN 30 connectivity.
For this to occur, CPE GW 40 is capable of, for example, distinguishing between different
DHCP sessions. This CPE GW 40 forwards DHCP session requests to the WAN 22 for WAN
addressed devices, e.g., cell phone 14, and handles other DHCP session requests locally
for locally addressed devices, e.g., PC 10, by allocating private IP addresses. The
CPE GW 40 therefore also includes a router 302 which includes a route entry table
310. The route entry table 310 can, for example, be populated with WAN assigned addresses
snooped from DHCP signaling messages between the WAN addressed devices on the LAN
30 side and the DHCP server 32 on the WAN 22 side. Once IP addresses are stored in
the route entry table 310, local traffic, e.g., IP packets transmitted from a device
connected to the LAN 30 toward a WAN addressable device connected to the same LAN
30, can be handled as local traffic and routed as needed, e.g., without the traffic
first going out to the WAN 22 and then returning to LAN 30.
[0024] Using the exemplary devices described in Figures 2 and 3, exemplary systems and methods
for implementing a LAN 30 which includes both locally addressable device and WAN addressable
devices connecting to a WAN 22 through a CPE GW 40 will now be described. Initially
all end user devices, e.g., PCs 10, 12, cell phone 14 and PDA 16, connect using the
same LAN 30. Communications can be wired or wireless between these devices and the
CPE GW 40. As the locally addressed devices, e.g., PCs 10 and 12, connect to the LAN
30 by communicating with the CPE GW 40, the devices 10 and 12 are determined to be
locally addressed devices and are assigned local IP addresses, e.g., 192.168.x.x,
by NAT function 306. Additionally, using the Address Resolution Protocol (ARP) Media
Access Control (MAC) addresses for the locally addressed devices are determined (as
described above in the Background Section) and used by the CPE GW 40 to route IP packets
to locally addressable devices connected to the LAN via layer 2 switching. On the
other hand, as WAN addressable devices connect to the LAN 30, the devices are determined
to be WAN addressable devices. Their IP address requests are forwarded on to, e.g.,
an associated DHCP server or the like for IP address assignment. The CPE GW 40 stores
the returned IP address in the route entry table 310 and uses that address to route
local traffic addressed to such WAN addressable devices via layer 3 switching. This
determination, i.e., as to whether a connecting device is a locally addressable device
or a WAN addressable device, is, for example, performed by the router 302 section
of the CPE GW 40 in conjunction with the DHCP decision function 304. One exemplary
method for determining if received traffic from the LAN 30 side needs to go through
NAT function 306, would be to look at the source address. If the source address is
on the local subnet, the router 302 could forward the traffic to NAT function 306,
otherwise the traffic would be from a WAN addressable device with its own assigned
WAN address which could bypass NAT function 306.
[0025] For WAN addressed devices, e.g., cell phone 14 and PDA 16, the exemplary CPE GW 40
has the ability receive network access requests. Using exemplary systems and methods,
the CPE GW 40 is capable of forwarding IP address requests from WAN addressable devices
through a variety of methods as will be described in more detail below. Upon receiving
a message(s) from cell phone 14, the router 302 and the DHCP decision function 304
determine if the received message is a DHCP message requesting an IP address from
the WAN 22 side, i.e., if device 14 is a WAN addressable device. If so, then the CPE
GW 40 forwards the DHCP message(s) to an IP edge node 26 on the WAN 22 side through
the communications interface 308. An exemplary pattern for the initial DHCP messages
can be described as shown in Figure 4. Therein, a client 402 sends a DHCP Discovery
message 406 to a DHCP server 404. The DHCP server 404 responds with a DHCP Offer message
408. The client 402 then responds with a DHCP Request message 410 which is then followed
by the DHCP server 404 responding to the request with a DHCP Acknowledge message 412.
More information regarding DHCP messages can be found in RFC 2131, which can be found
at www.ietf.org and is incorporated herein by reference. Through the DHCP messaging
process, a DHCP server 32 assigns an IP address for the requesting cell phone 14 and
this IP address is then transmitted back to the CPE GW 40 which forwards this information
to cell phone 14. While forwarding these DHCP messages between the DHCP server 32
and cell phone 14, the CPE GW 40 snoops address information from these DHCP messages.
As a result of this snooping, the CPE GW 40 inserts a route entry locally into route
entry table 310 for the given IP address for cell phone 14.
[0026] Regarding DHCP messages, when a device obtains its IP address, the device typically
gets additional information from the DHCP signaling process. More specifically, the
device receives information about the subnet to which it belongs, e.g., the device's
subnet mask, and the address of the router acting on the subnet, in this case CPE
GW 40. When a packet is sent within the subnet, ARP is used to get the MAC address
and the packet is sent directly to the device with the associated MAC address. For
packets sent to a destination outside of the subnet, the packet needs to be sent to
the router 302 in CPE GW 40. However, if the MAC address of the router 302/CPE GW
40 is not known (or stored), ARP is used, using the IP address of the router received
through DHCP to obtain the MAC address. For WAN addressable devices, this can cause
a complication, because the IP edge 26 sends the DHCP Offer. In the DHCP Offer message,
the IP edge includes its own IP address as the router address on the subnet. However,
when the WAN addressable device desires to send a packet, it must find the MAC address
of the CPE GW 40. This would normally lead the WAN addressed device to use ARP to
attempt to find the MAC address which matches the IP address supplied by the IP edge
26. Since the ARP is only broadcasted on the LAN 30, there is no match to the supplied
IP address, hence there is no device to answer the ARP message(s) and the transmission
of packets would fail.
[0027] According to exemplary embodiments, the CPE GW 40 can perform a proxy-ARP process
to address this issue as will now be described. When CPE GW 40 snoops the DHCP signaling,
the CPE GW 40 obtains knowledge of the router IP address transmitted by IP edge 26.
CPE GW 40 can use this snooped information to answer the ARP message(s) sent by the
WAN addressed device on behalf of IP Edge 26, by responding with the MAC address of
CPE GW 40. This results in packets being sent from the WAN addressed device going
to the CPE GW 40, which can then forward the packets as described in other exemplary
embodiments herein. Additionally, the CPE GW 40 can apply this technique for all addresses
on the subnet to which the WAN addressable device belongs. Alternatively, the CPE
GW 40 could replace the router address in the DHCP message(s), thus forcing the WAN
addressable device to use it as the gateway.
[0028] Once the locally addressed devices and the WAN addressed devices have connected to
LAN 30 and the CPE GW 40 has knowledge stored for uniquely identifying each device
connected to the LAN 30, data packets can be transmitted between these devices. For
example, to transmit IP packets from PC 10 with a locally assigned IP address of 192.168.0.1
to cell phone 14 with a WAN assigned IP address of 178.12.13.15, the IP packets go
from PC 10 to CPE GW 40 which then forwards the IP packets to cell phone 14, thus
keeping the information all locally routed within LAN 30. This occurs because the
CPE GW 40 is aware of the IP address of cell phone 14 from the stored, snooped IP
address associated with the cell phone's 14 earlier DHCP signaling session with the
DHCP server 32 associated with WAN 22.
[0029] For transmitting IP packets from cell phone 14 to PC 10, a similar process occurs
except that the PC's 10 default route for the subnet is known by the CPE GW 40 for
communications. In the case where local multicast and broadcast traffic is occurring,
e.g., for Universal Plug and Play (UPNP), the traffic is handled through local switching
within the LAN 30. WAN addressed devices are also able to receive such traffic on
local LAN 30. Also, for the WAN addressed devices, at some point the DHCP session
typically ends, i.e., because the address lease expired or connectivity is lost due
to mobility issues, and the earlier stored route entry in the route entry table 310
is then deleted. Until a new DHCP session occurs, the CPE GW 40 routes subsequent
IP packets through the communications interface 308 on the WAN 22 side to the IP Edge
26.
[0030] As described above, there are various exemplary methods for CPE GW 40 to determine
how to obtain a WAN IP address associated with WAN 22 for WAN addressed devices. According
to one exemplary embodiment, every WAN addressed device in the household is associated
with a virtual LAN (VLAN). In this context a VLAN can be considered to be a logical
network with the endpoints being the CPE GW 40 and the WAN addressed device. So for
the system shown in Figure 3, the cell phone 14 would be associated with a first VLAN
with the CPE GW 40 and the PDA 16 would be associated with a second VLAN with the
CPE GW 40. The PCs 10 and 12 would be connected as described above. The identity associated
with each VLAN would inform the CPE GW 40 that the received DHCP messages would need
to go out to WAN 22 for IP address assignment. Also the identifying information associated
with each VLAN (or the subsequently obtained WAN IP addresses) could be used for IP
packet transfer between devices connected_locally, e.g., PC 10 and cell phone 14.
Alternatively, a single VLAN could be used for all of the devices desiring to obtain
a WAN address.
[0031] According to another exemplary embodiment, the DHCP Discovery message can be modified
to include a new option field to enable CPE GW 40 to obtain an IP address for WAN
addressed devices. This new option field can include a flag for allowing a device,
e.g., CPE GW 40, to know that a WAN addressed device in its network is requesting
a WAN 22 IP address. Upon receiving this message the router 302 in conjunction with
the DHCP decision field would see the new option field in the DHCP Discovery message
and forward the message toward WAN 22 through the communications interface 308 with
the end result being the return of an IP address which would be associated with the
requesting device and stored in route entry table 310.
[0032] According to another exemplary embodiment, other means of uniquely identifying a
device which desires a WAN address can be used for routing traffic locally in a LAN
30 as well as being used as a flag for CPE GW 40 to request a WAN address associated
with WAN 30. For example, cell phone 14 can have a unique identifier, e.g., a media
access control (MAC) address, which is known to the CPE GW 40. The CPE GW 40 could
receive this unique identifier by an outside service provider or through some type
of manual provisioning. Once the unique identifier is stored in the CPE GW 40, methods
similar to those described above could be used for obtaining a WAN address when requested.
Also similar methods for routing local traffic between locally addressed devices and
WAN addressed devices on LAN 30 as described above can be used.
[0033] According to another exemplary embodiment, a WAN addressed device connecting through
a CPE GW 40 can use a DHCP authentication process to obtain a WAN IP address. For
example, using the exemplary call flow diagram shown in Figure 5, a cell phone 14
desires a WAN 22 IP address and transmits a DHCP discovery with authentication message
502. The CPE GW 40 identifies that the cell phone 14 is using a DHCP based authentication
and thereby knows that cell phone 14 wants to request a WAN 22 IP address. The CPE
GW 40 forwards the DHCP discovery with authentication message 502 to the IP edge node
26 associated with the WAN 22. The IP edge node 26 then transmits an access request
message 504 which includes user credentials associated with cell phone 14 contained
within the DHCP discovery with authentication message 502 to RADIUS server 34. If
the RADIUS server 34 accepts the request, the request is acknowledged in access accept
message 506 and an IP session is authorized at 508. The IP edge node 26 then relays
the DHCP discovery message (with RADIUS attributes as a suboption) 510 to the DHCP
server 32. DHCP server 32 assigns a WAN 22 IP address to the cell phone 14 and transmits
that offer back to the cell phone 14 (through the intervening nodes) as DHCP offer
message 512. After receiving DHCP offer message 512, cell phone 14 then responds with
a DHCP request message 514 which is forwarded by the CPE GW 40 to the DHCP server
32. The DHCP server 32 then completes this part of the process by transmitting a DHCP
acknowledgement message 516 back to the cell phone 14 through CPE GW 40. During this
exchange of DHCP messages, the CPE GW 40 snoops the IP address information as well
as other pertinent information for entry into entry table 310. For more information
regarding authentication of DHCP messages, the interested reader is directed to RFC
3118 which can be found at www.ietf.org and is incorporated herein by reference.
[0034] According to other exemplary embodiments, CPE GW 40 can include a firewall function
for protecting the LAN 30. All traffic incoming from the WAN 22 side (or alternatively
received communications from either side of the CPE GW 40) to the CPE GW 40 can be
processed by the firewall function prior to being forwarded to the intended device.
For example, traffic intended for WAN addressable device cell phone 14 would be received
by CPE GW 40, processed by the firewall function, bypass the NAT function 306 and
then be forwarded by router function 302 over the LAN 30 to cell phone 14.
[0035] The exemplary embodiments described above provide for messages and protocols involving
access routers and other network nodes. An exemplary network node 600 will now be
described with respect to Figure 6. Network node 600 can contain a processor 602 (or
multiple processor cores), memory 604, one or more secondary storage devices 606 and
an interface unit 608 to facilitate communications between network node 600 and the
rest of the network. The memory can be used for storage of exemplary items described
above such as the IP addresses and other information relevant from the DHCP communications
associated with the WAN addressed devices on a LAN. Thus, a network node according
to an exemplary embodiment may include a processor for transmitting and receiving
messages associated with at least forwarding communications between WAN addressed
devices and locally addressed devices on the same LAN.
[0036] Utilizing the above-described exemplary systems according to exemplary embodiments,
a method for acquiring IP addresses for devices in a network is shown in the flowchart
of Figure 7. Initially a method for allowing both network devices desiring a local
address and network devices desiring a wide area network (WAN) address to obtain Internet
Protocol (IP) addresses via a local area network (LAN) includes: receiving a message
from an end user device connected to the LAN wherein the end user device is requesting
an IP address in step 702; determining whether the end user device is a locally addressable
device or a WAN addressable device in step 704; forwarding the IP address request
toward a WAN if the end user device is the WAN addressable device in step 706; storing,
as route entry information, a returned IP address for the WAN addressable device in
step 708; and routing information locally over the LAN which is addressed to the WAN
addressable device using the stored route entry information in step 710.
[0037] The above-described exemplary embodiments are intended to be illustrative in all
respects, rather than restrictive, of the present invention. All such variations and
modifications are considered to be within the scope of the present invention as defined
by the following claims. Also, as used herein, the article "a" is intended to include
one or more items.
1. A method for allowing both network devices desiring a local address and network devices
desiring a wide area network (WAN) address to obtain Internet Protocol (IP) addresses
via a local area network (LAN) (30) comprising:
receiving a message from an end user device connected to said LAN (30) wherein said
end user device is requesting an IP address;
determining whether said end user device is a locally addressable device (10, 12)
or a WAN addressable device (14,16);
forwarding said IP address request toward a WAN if said end user device is said WAN
addressable device (14,16);
storing, as route entry information, a returned IP address for said WAN addressable
device (14,16); and
routing information locally over said LAN (30) which is addressed to said WAN addressable
device using said stored route entry information.
2. The method of claim 1, further comprising:
receiving said returned IP address for said WAN addressable device from a dynamic
host configuration protocol (DHCP) server and forwarding said IP address to said WAN
addressable device.
3. The method of claim 1, further comprising:
allocating an IP address locally and determining a default route for a subnet if said
end user device is said locally addressable device;
4. The method of claim 1, wherein said WAN addressable device forms a virtual LAN with
a customer premise equipment gateway and sends dynamic host configuration protocol
(DHCP) messages over said virtual LAN.
5. The method of claim 1, wherein said received message is a modified DHCP Discover message
which has an option field flagged for notifying a customer premise equipment gateway
to request a WAN IP address for said WAN addressable device.
6. The method of claim 1, wherein said step of determining further comprises:
providing unique identifying information for said WAN addressable device to a customer
premise equipment gateway and using said unique identifying information to determine
whether said end user device is a locally addressed device or a WAN addressed device.
7. The method of claim 1, wherein said step of forwarding said IP address request for
said WAN addressable device further comprises:
performing a dynamic host configuration protocol (DHCP) authentication process for
said WAN addressable device.
8. The method of claim 1, further comprising:
transmitting IP packets from a locally addressable end user device to said WAN addressable
device by routing said IP packets through a customer premise equipment gateway associated
with said LAN toward said WAN addressable device using said stored route entry information.
9. The method of claim 1, further comprising:
transmitting IP packets from said WAN addressable device to a locally addressable
device by routing said IP packets through a customer premise equipment gateway associated
with said LAN toward said locally addressable device.
10. The method of claim 1, further comprising:
ending a dynamic host configuration protocol (DHCP) session for said WAN addressable
device and deleting said stored route entry information.
11. The method of claim 9, further comprising:
routing subsequent IP packets through a wide area network (WAN) interface.
12. A communications node for allowing both network devices desiring a local address and
network devices desiring a wide area network (WAN) address to obtain Internet Protocol
(IP) addresses via a local area network (LAN) (30) comprising:
a router (302) for receiving a message from an end user device connected to said LAN
(30) wherein said end user device is requesting an IP address;
a dynamic host configuration protocol (DHCP) decision function (304) for determining,
in conjunction with router (302) whether said end user device is a locally addressable
device (10, 12) or a WAN addressable device (14,16);
a communications interface (308) for forwarding said IP address request toward a WAN
if said end user device is said WAN addressable device (14,16); and
wherein said router (302) stores, as route entry information, a returned IP address
for said WAN addressable device (14,16) and routes information locally over said LAN
(30) which is addressed to said WAN addressable device using said stored route entry
information.
13. The communications node of claim 12, wherein said communications node is a customer
premise equipment gateway.
14. The communications node of claim 12, wherein said locally addressable device is capable
of receiving and using a locally assigned IP address from said communications node.
15. The communications node of claim 12, wherein said WAN addressable device is not capable
of being assigned a local IP address from said communications node and further wherein
said WAN addressable device is capable of receiving and being assigned a forwarded
WAN assigned IP address.
1. Verfahren, um sowohl Netzwerkvorrichtungen, die eine lokale Adresse verlangen, als
auch Netzwerkvorrichtungen, die eine Weitverkehrsnetz-(WAN-)Adresse verlangen, zu
ermöglichen, Internetprotokoll-(IP)-Adressen über ein lokales Netzwerk (LAN) 30 zu
erlangen, umfassend:
Empfangen einer Nachricht von einer Endbenutzervorrichtung, die mit dem LAN (30) verbunden
ist, wobei die Endbenutzervorrichtung eine IP-Adresse anfordert;
Bestimmen, ob die Endbenutzervorrichtung eine lokal adressierbare Vorrichtung (10,
12) oder eine WAN-adressierbare Vorrichtung (14, 16) ist;
Weiterleiten der IP-Adressenanforderung zu einem WAN, wenn die Endbenutzervorrichtung
die WAN-adressierbare Vorrichtung (14, 16) ist;
Speichern einer zurückgesendeten IP-Adresse für die WAN-adressierbare Vorrichtung
(14, 16) als Leitwegeintragsinformation; und
lokal erfolgendes Leiten von Information, die an die WAN-adressierbare Vorrichtung
adressiert ist, über das LAN (30) unter Verwendung der gespeicherten Leitwegeintragsinformation.
2. Verfahren nach Anspruch 1, ferner umfassend:
Empfangen der zurückgesendeten IP-Adresse für die WAN-adressierbare Vorrichtung von
einem Server für das dynamische Host-Konfigurationsprotokoll (DHCP) und Weiterleiten
der IP-Adresse zu der WAN-adressierbaren Vorrichtung.
3. Verfahren nach Anspruch 1, ferner umfassend:
lokal erfolgendes Zuweisen einer IP-Adresse und Bestimmen eines Vorgabeleitwegs für
ein Teilnetz, wenn die Endbenutzervorrichtung die lokal adressierbare Vorrichtung
ist.
4. Verfahren nach Anspruch 1, wobei die WAN-adressierbare Vorrichtung ein virtuelles
LAN mit einem Teilnehmereinrichtungsgateway bildet und Nachrichten des dynamischen
Host-Konfigurationsprotokolls (DHCP) über das virtuelle LAN sendet.
5. Verfahren nach Anspruch 1, wobei die empfangene Nachricht eine modifizierte DHCP-Discover-Nachricht
ist, bei der ein Optionsfeld gesetzt ist, um einen Teilnehmereinrichtungsgateway zu
benachrichtigen, damit er eine WAN-IP-Adresse für die WAN-adressierbare Vorrichtung
anfordert.
6. Verfahren nach Anspruch 1, wobei der Schritt des Bestimmens ferner umfasst:
Bereitstellen eindeutiger Kennzeichnungsinformation für die WAN-adressierbare Vorrichtung
für einen Teilnehmereinrichtungsgateway und Verwenden der eindeutigen Kennzeichnungsinformation,
um zu bestimmen, ob die Endbenutzervorrichtung eine lokal adressierbare Vorrichtung
oder eine WAN-adressierbare Vorrichtung ist.
7. Verfahren nach Anspruch 1, wobei der Schritt des Weiterleitens der IP-Adressenanforderung
für die WAN-adressierbare Vorrichtung ferner umfasst:
Durchführen eines Authentifizierungsprozesses nach dem dynamischen Host-Konfigurationsprotokoll
(DHCP) für die WAN-adressierbare Vorrichtung.
8. Verfahren nach Anspruch 1, ferner umfassend:
Übertragen von IP-Paketen von einer lokal adressierbaren Endbenutzervorrichtung zu
der WAN-adressierbaren Vorrichtung durch Leiten der IP-Pakete durch einen dem LAN
zugeordneten Teilnehmereinrichtungsgateway zu der WAN-adressierbaren Vorrichtung unter
Verwendung der gespeicherten Leitwegeintragsinformation.
9. Verfahren nach Anspruch 1, ferner umfassend:
Übertragen von IP-Paketen von der WAN-adressierbaren Vorrichtung zu einer lokal adressierbaren
Vorrichtung durch Leiten der IP-Pakete durch einen dem LAN zugeordneten Teilnehmereinrichtungsgateway
zu der lokal adressierbaren Vorrichtung.
10. Verfahren nach Anspruch 1, ferner umfassend:
Beenden einer Sitzung des dynamischen Host-Konfigurationsprotokolls (DHCP) für die
WAN-adressierbare Vorrichtung und Löschen der gespeicherten Leitwegeintragsinformation.
11. Verfahren nach Anspruch 1, ferner umfassend:
Leiten nachfolgender IP-Pakete durch eine Weitverkehrsnetz-(WAN-)Schnittstelle.
12. Kommunikationsknoten, um sowohl Netzwerkvorrichtungen, die eine lokale Adresse verlangen,
als auch Netzwerkvorrichtungen, die eine Weitverkehrsnetz-(WAN-)Adresse verlangen,
zu ermöglichen, Internetprotokoll-(IP)-Adressen über ein lokales Netzwerk (LAN) 30
zu erlangen, umfassend:
einen Router (302) zum Empfangen einer Nachricht von einer Endbenutzervorrichtung,
die mit dem LAN (30) verbunden ist, wobei die Endbenutzervorrichtung eine IP-Adresse
anfordert;
eine Entscheidungsfunktion (304) für das dynamische Host-Konfigurationsprotokoll (DHCP)
zum Bestimmen in Verbindung mit dem Router (302), ob die Endbenutzervorrichtung eine
lokal adressierbare Vorrichtung (10, 12) oder eine WAN-adressierbare Vorrichtung (14,
16) ist;
eine Kommunikationsschnittstelle (308) zum Weiterleiten der IP-Adressenanforderung
zu einem WAN, wenn die Endbenutzervorrichtung die WAN-adressierbare Vorrichtung (14,
16) ist; und
wobei der Router (302) eine zurückgesendete IP-Adresse für die WAN-adressierbare Vorrichtung
(14, 16) als Leitwegeintragsinformation speichert und Information, die an die WAN-adressierbare
Vorrichtung adressiert ist, unter Verwendung der gespeicherten Leitwegeintragsinformation
lokal über das LAN (30) leitet.
13. Kommunikationsknoten nach Anspruch 12, wobei der Kommunikationsknoten ein Teilnehmereinrichtungsgateway
ist.
14. Kommunikationsknoten nach Anspruch 12, wobei die lokal adressierbare Vorrichtung in
der Lage ist, eine lokal zugeordnete IP-Adresse von dem Kommunikationsknoten zu empfangen
und zu verwenden.
15. Kommunikationsknoten nach Anspruch 12, wobei die WAN-adressierbare Vorrichtung nicht
in der Lage ist, eine lokale IP-Adresse von dem Kommunikationsknoten zugeordnet zu
bekommen, und wobei die WAN-adressierbare Vorrichtung ferner in der Lage ist, eine
weitergeleitete vom WAN zugeordnete IP-Adresse zu empfangen und zugeordnet zu bekommen.
1. Procédé destiné à permettre à des dispositifs de réseau désirant une adresse locale
et à des dispositifs de réseau désirant une adresse de réseau étendu (WAN) d'obtenir
des adresses de protocole Internet (IP) via un réseau local (LAN) (30), comprenant
les étapes ci-dessous consistant à :
recevoir un message en provenance d'un dispositif d'utilisateur final connecté audit
réseau LAN (30), dans lequel ledit dispositif d'utilisateur final demande une adresse
IP ;
déterminer si ledit dispositif d'utilisateur final est un dispositif à adresse locale
(10, 12) ou un dispositif à adresse de réseau WAN (14, 16) ;
acheminer ladite demande d'adresse IP vers un réseau WAN si ledit dispositif d'utilisateur
final est ledit dispositif à adresse de réseau WAN (14, 16) ;
stocker, en qualité d'informations d'entrée de chemin, une adresse IP renvoyée pour
ledit dispositif à adresse de réseau WAN (14, 16) ; et
acheminer des informations localement sur ledit réseau LAN (30), lesquelles sont adressées
audit dispositif à adresse de réseau WAN en faisant appel auxdites informations d'entrée
de chemin stockées.
2. Procédé selon la revendication 1, comprenant en outre l'étape ci-dessous consistant
à :
recevoir ladite adresse IP renvoyée pour ledit dispositif à adresse de réseau WAN
à partir d'un serveur de protocoles de configuration dynamique de l'hôte (DHCP) et
acheminer ladite adresse IP audit dispositif à adresse de réseau WAN.
3. Procédé selon la revendication 1, comprenant en outre l'étape ci-dessous consistant
à :
affecter une adresse IP localement et déterminer un chemin par défaut pour un sous-réseau
si ledit dispositif d'utilisateur final est ledit dispositif à adresse locale.
4. Procédé selon la revendication 1, dans lequel ledit dispositif à adresse de réseau
WAN forme un réseau LAN virtuel avec une passerelle d'équipement d'installation client
et envoie des messages de protocole de configuration dynamique de l'hôte (DHCP) sur
ledit réseau LAN virtuel.
5. Procédé selon la revendication 1, dans lequel ledit message reçu est un message de
détection de protocole DHCP modifié lequel présente un champ d'option marqué, en vue
de notifier une passerelle d'équipement d'installation client afin qu'elle demande
une adresse IP de réseau WAN pour ledit dispositif à adresse de réseau WAN.
6. Procédé selon la revendication 1, dans lequel ladite étape de détermination comprend
en outre l'étape ci-dessous consistant à :
fournir des informations d'identification uniques, pour ledit dispositif à adresse
de réseau WAN, à une passerelle d'équipement d'installation client, et utiliser lesdites
informations d'identification uniques en vue de déterminer si ledit dispositif d'utilisateur
final est un dispositif à adresse locale ou un dispositif à adresse de réseau WAN.
7. Procédé selon la revendication 1, dans lequel ladite étape consistant à acheminer
ladite demande d'adresse IP pour ledit dispositif à adresse de réseau WAN comprend
en outre l'étape ci-dessous consistant à :
mettre en oeuvre un processus d'authentification de protocole de configuration dynamique
de l'hôte (DHCP) pour ledit dispositif à adresse de réseau WAN.
8. Procédé selon la revendication 1, comprenant en outre l'étape ci-dessous consistant
à :
transmettre des paquets IP, d'un dispositif d'utilisateur final à adresse locale audit
dispositif à adresse de réseau WAN, en acheminant lesdits paquets IP à travers une
passerelle d'équipement d'installation client associée audit réseau LAN vers ledit
dispositif à adresse de réseau WAN, en faisant appel auxdites informations d'entrée
de chemin stockées.
9. Procédé selon la revendication 1, comprenant en outre l'étape ci-dessous consistant
à :
transmettre des paquets IP, dudit dispositif à adresse de réseau WAN à un dispositif
à adresse locale, en acheminant lesdits paquets IP à travers une passerelle d'équipement
d'installation client associée audit réseau LAN vers ledit dispositif à adresse locale.
10. Procédé selon la revendication 1, comprenant en outre l'étape ci-dessous consistant
à :
mettre fin à une session de protocole de configuration dynamique de l'hôte (DHCP)
pour ledit dispositif à adresse de réseau WAN et supprimer lesdites informations d'entrée
de chemin stockées.
11. Procédé selon la revendication 9, comprenant en outre l'étape ci-dessous consistant
à :
acheminer des paquets IP subséquents via une interface de réseau étendu (WAN).
12. Noeud de communication destiné à permettre à des dispositifs de réseau désirant une
adresse locale et à des dispositifs de réseau désirant une adresse de réseau étendu
(WAN) d'obtenir des adresses de protocole Internet (IP) via un réseau local (LAN)
(30), comprenant :
un routeur (302) pour recevoir un message en provenance d'un dispositif d'utilisateur
final connecté audit réseau LAN (30), dans lequel ledit dispositif d'utilisateur final
demande une adresse IP ;
une fonction de décision de protocole de configuration dynamique de l'hôte (DHCP)
(304) pour déterminer, conjointement au routeur (302), si ledit dispositif d'utilisateur
final est un dispositif à adresse locale (10, 12) ou un dispositif à adresse de réseau
WAN (14, 16) ;
une interface de communication (308) pour acheminer ladite demande d'adresse IP vers
un réseau WAN si ledit dispositif d'utilisateur final est ledit dispositif à adresse
de réseau WAN (14, 16) ; et
dans lequel ledit routeur (302) stocke, en qualité d'informations d'entrée de chemin,
une adresse IP renvoyée pour ledit dispositif à adresse de réseau WAN (14, 16), et
achemine les informations localement sur ledit réseau LAN (30), lesquelles sont adressées
audit dispositif à adresse de réseau WAN en faisant appel auxdites informations d'entrée
de chemin stockées.
13. Noeud de communication selon la revendication 12, dans lequel ledit noeud de communication
est une passerelle d'équipement d'installation client.
14. Noeud de communication selon la revendication 12, dans lequel ledit dispositif à adresse
locale est apte à recevoir et à utiliser une adresse IP affectée localement à partir
dudit noeud de communication.
15. Noeud de communication selon la revendication 12, dans lequel ledit dispositif à adresse
de réseau WAN n'est pas en mesure de se voir affecter une adresse IP locale à partir
dudit noeud de communication, et en outre dans lequel ledit dispositif à adresse de
réseau WAN est en mesure de recevoir et de se voir affecter une adresse IP acheminée
affectée à un réseau WAN.